Method and means for electrolyzing saline solutions.



. E. A. ALLEN.

METHOD AND MEANS FOR ELEGTROLYZING SALINB SOLUTIONS.

APPLICATION FILED .TAN.6. 1912.

Patented Sept. 1, 1914.

[rz/ve 11. to 7'.- Edwardfllw UNITED sTATEs PATENT oEEroE.

EDWARD A. ALLEN, OF RUMFORD FALLS, MAINE.

`METHOD AND MEANS FOR ELECTBOLYZING SALINE SOLUTIONS.

Specication of Letters Patent.

Patented sept. 1, 1914.

'Application led January 6, 1912. Serial No. 669,792.

`To all 'wie om 'it may concern f methods of electrolyzing saline solutions for the production of chlorin and hydrates such as sodium hydrate or potassium hydrate.

The primary object of the invention is to solution being electrolyzed.

On the accompanying drawing, Figure l illustrates a longitudinal section through a cell embodying the invention. Fig. 2 represents a transverse vertical section through the same. Fig. 3 represents a horizontal section immediately above the upper diaphragm, the diaphragm being broken away at the left end to show the supporting grid which is located beneath it. Fig. l illustrates two of the carbon anodes and shows how their upper surfaces are iiuted or grooved. 1

According to my invention, I propose to employ two diaphragms which are separated to provide a space for the electrolyte, and through which the latter is caused to iiow, such electrolyte consisting of brine, that is, water saturated with salt or potassium chlorid, or other solution which may be electrolyzed. The anode, which is located on the outer side of one of the diaphragms, is formed of carbon blocks, whereas the cathode, which is located on the outside of the other diaphragm, consists of a layer of mercury, with which the cations given off during the electrolyzation of the brine unite to form amalgam. Necessarily the diaphragms are arranged horizontally, the carbon anode being underneath the lower diaphragm and Vthe mercury cathode being above the upper diaphragm and completely covering it. The lower diaphragm is preferably formed of some material such as asbestos cloth through which the electrolyte will percolate, not too freely and yet suiiciently to prevent the chlorin which is given off at the anode from Vpassing through it to Contact with the electrolyte in the space between the diaphragme. Above the layer of mercury there is contained a body of water into which project numerous conductors or electrodes constltute the cathode of a primary cell consisting of the mercury and amalgam,l thebod of water, and the conductors or elec tro es. The upper diaphragm is preferabl 'j relatlvely stiff, belng made of asbestos clotl coated or impregnated with cement s o as to' be nearly` impervious to thepassageiof liquor therethrough. If, however, it be 'made of several untreated layers of asbestos cloth, the mercury itself will form a seal to prevent the passage of the electrolyte therethrough upward or the passage of the water therethrough downward. prevent the absorption of the chlorin in the flow through the space between the dia- In operation, the electrolyte is caused to phragms, and, current being passed from the carbon anode to the conductors last referred to, the following action takes lace The saline. solution is decomposed, c lorin being given olf at the carbon anode and being carried away in any convenient manner, and on the surface of the 'upper diaphragm, where the layer of mercury rests, the metal, which is liberated (z. e. sodium, potassium or the like), unites with the mercury to form an amalgam. The amalgam being lighter than the mercury, slowly rises to the top thereof, so that, when thejamalgam comes in contact with the water, the metal is freed and unites with the water, forming the hydrate of the metal, accordingV to the well known formulae, hydrogen Abeing of course liberated. Suliicient hydrostatic pressure is maintained with the electrolyte compartment to sustain the upperdiaphragm with its weightA of mercury Vand water.

Proceeding to `amore detailed descriptionV of the cell, the body thereof consists of a rectangular tank comprising a bottom wall a, end walls a and side walls a?. The cell body may be of wood, slate or other suitable material. Upon the bottom of the cell body, l place cross pieces b of wood, slate or other suitable material upon which rest two longitudinal carbon bars c which are connected by cylindrical carbon bars or conductorsd, the

latter being tapered as shown in Fig. 2. Theends of these carbon conductors d project through the side walls of the cell body and are connected by bus bars or otherl suitable. forms of conductors to which may be con-V nected the conductors from the dynamo. Resting upon the longitudinal bars c and connected thereto by carbon dowels c are the diaphragm flat carbon plates e which constitute the anode of the cell. The upper faces of these anode plates are groove or corrugated as illustrated in Fig. 3, the bottom walls of said grooves being preferably inclined to the horizontal. Extending horizontally across the cell are the two diaphragms f and g, the former being supported in part by the u pper faces of the anode plates.. The d iaphragms are separated b a grld conslstlng of a rectangular frame L aving bars it projecting from its sides across the cell, ca ch cross bar terminating short of the opposite side of the frame so as to form a tortuous ath in which the electrolyte will How. greferably the side walls .of the cell are'divided in a horizontal plane so that the grid may be placed between the two sections thus formed, and the outer edges or margins of the diaphragme are secured to the frame of the grid so as to constitute with it a removable unit. Between the edges of the diaphragm and the adjacent surfacesl of the cell body, I interpose strips of insulatlng material as indicated at c'. Fig. 1 that the cross bars k preferably diamond shaped in cross section. The space y' between the two diaphragms I term the electrolyte compartment, the space within the cell body be ow the lower diaphragm indicated at la being designated the anode compartment, and the space m above the u per diaphragm f being called the cathocliJ compartment. As previously stated, the lower diaphra m g is preferably made of one or more layers of asbestos cloth through which the electrolyte, which is introduced into the electrolyte com artment, will percolate slowly. To retard t e flow or percolation therethrough, the diaphragm may then have a thin skin coat of, or be impregnated with, cement, asbestos liber or the like. The upper diaphragm f rests upon the cross 'bars of the grid 7L and it is pre erably made of one or more layers of asbestos cloth impregnated with cement.

Projecting into one end of the electrolyte compartment is an inlet pipe n leading from a standpipe n into which the brine is delivered from any convenient source. The brine is maintained at a height in the standpipe to insure hydrostatic pressure in the electrolyte compartment suiiicient to prevent the diaphragm f from sagging materially between the cross bars of the grid under the weight of the mercury and the water. From the electrolyte compartment extends a gooseneck pi e n2 to conduct away the impoverished solution to some tank where it is again supplied or enriched with salt. The electrolyte Hows constantly through the electrolyte compartment j and follows the tortuous path hereinbefore referred to. Above the u per f is a layer 0 of mercury, w lch in actual practice may be from one-half to It will be seen from. of the grid are' one inch thick and which is in contact with the entire up er exposed surface of said diaphragm. bove the mercury there is a body of water indicated at p into which project numerous terminals or electrodes g depending from cross bars r. Each terminal consists of a thin plate of iron or copper extending across the cell, as shown in igs. l and 2. The cross bars 9 are all connected to a suitable bus bar or other terminal from which conductors lead to thedynamo. i Wa.- ter is introduced partment of the cell through an inlet pipe a and the hydrate solution passes out through an overow plipe t. The chlorin, which is given oi in t e anode compartment, is conf ducted away by means of a pipe u, and such electrolyte as percolates through the lower diaphragm g 1s conducted away from the bottom of the anode compartment by a pipe c, which is water sealed as indicated at w so that the chlorin pipe a may with a vacuum system.

yI desire to call attention to the fact that there is no mechanical operation connected with the cell except the delivery of the electrolyte and of the water to their several compartments. The metal, which is given ofi' in contact with the mercury cathode, forms amalgam which, being of a less. specific gravity than the mercury, rises to the upper surface into contact with lthe water. A scc-` be connecte oud electrolytic action thereupon takes placa.

producln an electric current as in mary ce and, as a result, the volta quired to operate the cell as a whole terially reduced. The potassium, etc.) bein liberated from the mercury unites with t e water and forms a hydrate. This action all occurs in thejsme com artment of the cell.

a pri,- ge re- 1s maaving thus explained the naturefof my' said invention and described a wayfof'JJ-0.11'y structing and using the same, i without attempting to set forth all oft e forms in which it may be made or allnof:y

1. '1 he herein described process of ,electrolyzlng saline solutions, which consists inl the inner confronting faces of opposed horibringing a body of solution into contact with zontal diaphragms, passing a current of electricity therethrough, liberating chlorin at an unlmmersed anode outside of one ofsaid diaphragms so that it is unabsorbed by said body of electrolyte, liberating the metal in contact with the lower surface of a mercury cathode outside of and`in contact with the other diaphragm to amalgamate with said mercury, and liberating the said metal at the upper surface of said cathode in the presence of water.

2. The herein described process of electrolyzing saline solutions, which includes passing a current of electricity upwardly into 1 the cathode combase metal (sodium,

lio

from an anode through such solution andY through a horizontal diaphragm, a layer of mercury, and a body of water to a terminal electrode, all in the order named, liberating the metal in said solution in contact with the under face of said cathode to amalgamate therewith, liberating said metal at the upper surface of said cathode in the presence of water to form a hydrate, and liberating chlorin at a point below the body of saline solution and out of contact therewith.

3. In an electrolytic cell, the combination of horizontal confronting diaphragms forming an electrolyte compartment between them, a carbon anode below and in contact with the lower diaphragm, and a layer of mercury resting on the upper diaphragm and constituting the cathode.

4. An electrolytic cell, comprising a cell body, separated horizontal diaphragms in said body forming a compartment between them for the electrolyte, an anode compartment below them, and a cathode compartment above them, an anode below and in contact with the lower diaphragm, a mercury cathode above the upper diaphragm and in contact therewith, and a body of water above and in contact with the cathode.

5. An electrolytic cell, comprising a body, separated diaphragms forming a compartment for the electrolyte, a grid between said diaphragms, an anode on which the lower diaphragm rests, a mercury cathode covering the upper diaphragm, terminal electrodes, means for circulating electrolyte through said electrolyte compartment, and means for supplying a body of water to said cell to contact with said terminal electrodes and said mercury cathode.

6. An electrolytic cell comprising a cell body, a substantially flat anode having grooves or passageways, a diaphragm contacting with the upper face of the anode, a secondy diaphragm parallel to and separated from the other diaphragm to form a separate compartment for the circulation of the elec trolyte, a mercury cathode resting upon the upper diaphragm, spacing devices between the two diaphragms, terminal electrodes above and separated from the mercury cathode, provisions for circulating electrolyte through the said compartment, and provisions for supplying water to the cell body, to provide a body of water in contact with said oathode'and said terminal electrodes, and for removing hydrate from said cell.

In testimony whereof I have aflixed my signature, in presence of two witnesses.

EDWARD A. ALLEN. Witnesses:

ETHEL M. BRAINERD, JUDiTH C. THOMAS. 

